Incrementally Computing Minimal Unsatisfiable Cores of QBFs via a Clause Group Solver API

  • Florian LonsingEmail author
  • Uwe Egly
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9340)


We consider the incremental computation of minimal unsatisfiable cores (MUCs) of QBFs. To this end, we equipped our incremental QBF solver DepQBF with a novel API to allow for incremental solving based on clause groups. A clause group is a set of clauses which is incrementally added to or removed from a previously solved QBF. Our implementation of the novel API is related to incremental SAT solving based on selector variables and assumptions. However, the API entirely hides selector variables and assumptions from the user, which facilitates the integration of DepQBF in other tools. We present implementation details and, for the first time, report on experiments related to the computation of MUCs of QBFs using DepQBF’s novel clause group API.


Boolean Formula Selector Variable Unit Clause Bound Model Check Conformant Planning 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Knowledge-Based Systems Group Vienna University of TechnologyViennaAustria

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